Boiler construction.



D. D. SHIERK.

BOILER CONSTRUCTION. APPLICATION FILED OUT. 6, 1911.

Patented Oct. 22, 1912.

UNITED STATES PATENT curios.

DEARELL D. SHIERK, 0F ROCKFORD, ILLINOIS, ASSIGNOR OF ONE-HALF TOWILLIAM C. FARQUHAR, OF ROCKFORD, ILLINOIS.

To all whom it may concern:

Be it known that I, DEARELL D. stimuli, a citizen of the United States,residing at Rockford, in the county of lVmnebago and State of Illinois,have invented certaln new and useful Improvements in BoilerConstruction, of which the following is a specification.

The object of this invention is to overcome the objection to theordinary construction of flue boilers, in which the flues connected tothe back flue sheet, are burned out and leak, this often leading togreat damage. I overcome these objections by expanding the back fluesheet inward forming a flange to which the flue is connected, therebyremdving' the joint from the fire.

In the accompanying drawings. Figure 1 is a transverse section throughthe fire box of a locomotive boiler showing the back flue sheet and theflue openings. Fig. 2 1s a section on line a a Fig. l.

The boiler shown in Fig. l, with the exception of the connection of theflues with the back flue sheet is of the ordinary 1000-. motiveconstruction and is illustrated to show the location of my Improvements.

The rear flue sheet 1 of the boiler is formed with an inwardly extendingflange or nipple 2 expanded from the metal forming the flue sheet and isprovided with external screw-threads 3. A shoulder 4 is formed at thebase of the screw-threads.

A flue 5 has one end provided with internal screw-threads 6. The flue isthreaded over and upon the flange or nipple 2 and is turned hard againsta Washer '7 placed against the shoulder 4 thereby forming a water tightjoint. through an opening. in the head flue sheet 8 and is rolled in theusual manner.

- Heretofore boiler flues have been beaded Specification of LettersPatent. Application filed October 6, 1911.

at this The flue 5 is inserted Patented Oct. 22, 1912. Serial No.653,241.

against the outer face of the rear flue sheet in order to make a tightjoint. The heat coming in contact with the end of the flue point wouldsoon expand the bead from the flue sheetv and cause a-lealo. The fluewould be beaded-again and again until the material for forming the beadWasdestroyed or the flue sheet rendered Worthless. It is a known fact.that a flue, a short distance from the rear fiue'sheet was as good asnew, therefore it has been the common usage 'to cut ofl the burned endofthe flue and Weld on a section to t-akethe place of the burned section.4

My improvements enable me to locate the joint 9 between the flange andthe flue some distance along the direction of theflue so as to remove itfrom the action of the fierce heat generated in the firebox, and bysodoing, the flue will never burn out.

As the flange 2 is formed from the material of the rear flue sheet thereis no joint which is subjected to the fire, therefore the flange willlast as long as the flue sheet.

Iclaim as my invention.

In a boiler, the combination with a flue sheet having an inturnedintegral nipple that is externally threaded, and has an external annularshoulder at the end of the threads, of a flue having one end internallythreaded and screwed upon the nipple, and 4 a packing gasket surroundingthe ni ple and interposed between the shoulder an the adjacent end ofthe flue.

In testimony'whereof I have hereunto set my hand in presence of twosubscribing witv nesses.

DEARELL D. SHIERK.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

- Washington, D. G.

